Crocodiles listen to classical music in MRI scanner

May 3, 2018, Ruhr-Universitaet-Bochum
For the first time Mehdi Behroozi, Felix Ströckens and Xavier Helluy (from the left) examined a cold-blooded reptile using functional MRI. (c) RUB, MarquardThis image may only be used for reporting about the Ruhr-Universitaet Bochum in the context of the press release "Crocodiles Listen to Classical Music in MRI Scanner" published in May 2018.

Crocodiles count among the most ancient species of vertebrates and have barely changed over the space of more than 200 million years. Accordingly, they constitute a link between dinosaurs and bird species today. "Analyses of crocodile brains thus provide deep insights into the evolution of the nervous system in mammals and may help us understand at which point certain brain structures and behaviours associated therewith were formed," explains Felix Ströckens.

The objective pursued by the team of researchers from the Iran, South Africa, France, and Germany was to study Nile crocodiles and to ascertain the way is processed in their brain. To this end, they deployed functional MRI (fMRI) – a method that is routinely used in clinical diagnostics and research, but which has never yet been utilised to study a cold-blooded reptile. "In the first step, we had to overcome a number of technical obstacles," says research team member Mehdi Behroozi. "For example, we had to adjust the scanner to the crocodile's physiology, which differs massively from that of mammals in several aspects."

Subsequently, the researchers exposed the animals to various visual and , including classical music by Johann Sebastian Bach. At the same time, they measured the animals' brain activity. The results have shown that additional brain areas are activated during exposure to complex stimuli such as – as opposed to exposure to simple sounds. The processing patterns strongly resemble the patterns identified in mammals and birds in similar studies.

Consequently, the researchers assume that fundamental neuronal processing mechanisms of formed at an early evolutionary stage and that they can be traced back to the same origins in all vertebrates.

By successfully deploying fMRI for the examination of a reptile for the first time worldwide, the researchers, moreover, demonstrated that the method does work for poikilothermic organisms. This non-invasive technology can thus be used for many other species that have not yet been studied in depth.

Explore further: Optimized perception in the twilight zone

More information: Mehdi Behroozi et al. Functional MRI in the Nile crocodile: a new avenue for evolutionary neurobiology, Proceedings of the Royal Society B: Biological Sciences (2018). DOI: 10.1098/rspb.2018.0178

Related Stories

Optimized perception in the twilight zone

April 11, 2018

In the pre-industrial age, twilight was a dangerous time for humans due to higher risk of encountering nocturnal predators. The ability to see in weak light conditions was therefore at a clear evolutionary advantage. Neuroscientists ...

New evidence for warm-blooded dinosaurs

July 18, 2013

University of Adelaide research has shown new evidence that dinosaurs were warm-blooded like birds and mammals, not cold-blooded like reptiles as commonly believed.

This is your brain on Vivaldi and Beatles

August 7, 2013

Listening to music activates large networks in the brain, but different kinds of music are processed differently. A team of researchers from Finland, Denmark and the UK has developed a new method for studying music processing ...

Recommended for you

Microplastics may enter foodchain through mosquitoes

September 19, 2018

Mosquito larvae have been observed ingesting microplastics that can be passed up the food chain, researchers said Wednesday, potentially uncovering a new way that the polluting particles could damage the environment.

In a tiny worm, a close-up view of where genes are working

September 19, 2018

Scientists have long prized the roundworm Caenorhabditis elegans as a model for studying the biology of multicellular organisms. The millimeter-long worms are easy to grow in the lab and manipulate genetically, and have only ...

Social animals have tipping points, too

September 18, 2018

In relatively cool temperatures, Anelosimus studiosus spiders lay their eggs and spin their webs and share their prey in cooperative colonies from Massachusetts to Argentina. Temperatures may vary, but the colonies continue ...

Why do we love bees but hate wasps?

September 18, 2018

A lack of understanding of the important role of wasps in the ecosystem and economy is a fundamental reason why they are universally despised whereas bees are much loved, according to UCL-led research.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.